Generally, a control lever device for operating the brake is used with a flat type handle bar or a drop type handle bar. The control lever device for the flat type handle bar is mounted thereon in the vicinity of the grip at each end of the handle bar, and that for the drop type handle bar is mounted on each bent portion at the handle bar through a box-like shaped bracket member.
The control lever device, especially for the drop type handle bar, is operated in such a manner that a driver retains his fingers to the grip of the control lever while gripping by his hand the bent portion of the handle bar or the bracket member at the lever device, thereby turning the lever around the pivot point thereof and actuating the operating device.
The fingers of various drivers are different in length due to sex distinction, age or other individual differences, whereby a distance between the handle bar and the grip at the control lever, i.e., a grip dimension, need be changed correspondingly to a size of the driver's hand.
Conventionally, the bracket member has at the front wall thereof a threaded bore, and an adjusting bolt is screwed with the threaded bore and abuts at the tip against a boss of the control lever, the bolt being screwed forward or backward to adjust the grip dimension.
In such construction, the bolt projects at its head from the front wall of the bracket member, so that the control lever device, especially when mounted on the bent portion of the drop type handle, creates the following problem.
The driver, when driving the bicycle of the drop type handle bar, at a middle speed steers the handle gripping the bracket member. Hence, the projecting head of the adjusting bolt catches his palm, which is very dangerous. Also, an air resistance against the bicycle's running increases to an extent of the projecting head.
The adjusting bolt, however, must be mounted on the front wall of the bracket member due to the fact that the lever, in the conventional control lever device, is pivoted to the bracket member at the side walls thereof and in proximity to a side of being mounted to the handle bar.
In detail, the lever is biased unidirectionally by a return spring provided at the operating device, such as the brake, so that the grip dimension may be defined by abutment of the lever against the adjuster through the function of the return sping.
Hence, the adjuster must be provided forwardly in the swinging direction of the lever operated by the return spring.
However, the lever at the conventional device is pivoted to the bracket member in proximity to its mounting side to the handle bar, so that, when the adjuster is provided at the bracket member, the position where the adjuster is to be mounted forwardly in the direction of the swinging motion of the lever by the return spring, is limited to the front wall of the bracket member.
The adjusting bolt requires an allowance of adjustment, and the bracket member, which is made usually from a metallic plate, is smaller in thickness, whereby the adjuster inevitably projects outwardly from the front wall.
It is a remedy for the above that the projected head of the adjuster is made round to avoid the danger of hurting the driver's palm. The head, however, remains projected which is uncomfortable, resulting in driver fatigue and reduced controllability.